Rename fe_length to be fe_logi_length to distinguish it from the
fe_phys_length field.
If the extent's physical length is different from its logical length
(if FIEMAP_EXTENT_DATA_COMPRESSED is set) then use the fe_phys_length
for the physical length. If FIEMAP_EXTENT_DATA_COMPRESSED is unset,
then continue to use fe_logi_length for the extent length, but set
fe_phys_length = fe_logi_length to simplify the rest of the code.
Signed-off-by: Andreas Dilger <adilger@xxxxxxxxx>
---
lib/ext2fs/fiemap.h | 2 +-
misc/filefrag.c | 62 +++++++++++++++++++++++++++++++++++++--------------
2 files changed, 46 insertions(+), 18 deletions(-)
diff --git a/lib/ext2fs/fiemap.h b/lib/ext2fs/fiemap.h
index df973da..3cf32f7 100644
--- a/lib/ext2fs/fiemap.h
+++ b/lib/ext2fs/fiemap.h
@@ -16,7 +16,7 @@ struct fiemap_extent {
* the extent from the beginning of the file */
__u64 fe_physical; /* physical offset in bytes for the start
* of the extent from the beginning of the disk */
- __u64 fe_length; /* length in bytes for this extent */
+ __u64 fe_logi_length; /* logical length in bytes for this extent */
__u64 fe_phys_length; /* physical length in bytes for this extent,
* undefined if DATA_COMPRESSED not set */
__u64 fe_reserved64;
diff --git a/misc/filefrag.c b/misc/filefrag.c
index 7096abb..6cefaf4 100644
--- a/misc/filefrag.c
+++ b/misc/filefrag.c
@@ -133,10 +133,14 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
unsigned long long expected, int blk_shift,
ext2fs_struct_stat *st)
{
- unsigned long long physical_blk;
- unsigned long long logical_blk;
- unsigned long long ext_len;
- unsigned long long ext_blks;
+ unsigned long long logical_blk; /* logical starting block of file */
+ unsigned long long logical_len; /* logical length of extent in blocks */
+ unsigned long long logical_unit;/* logical length to end of extent, may
+ * not be logical_len-1 if extent isn't
+ * aligned to requested block size */
+ unsigned long long physical_blk;/* physical starting block in LUN */
+ unsigned long long physical_len;/* physical length of extent in blocks*/
+ unsigned long long physical_unit;/* physical length to end of extent */
__u32 flags, mask;
char buf[256] = "";
@@ -145,10 +149,20 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
if (flags & FIEMAP_EXTENT_DATA_INLINE)
blk_shift = 0;
- ext_len = fm_extent->fe_length >> blk_shift;
- ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
logical_blk = fm_extent->fe_logical >> blk_shift;
- physical_blk = fm_extent->fe_physical >> blk_shift;
+ logical_len = fm_extent->fe_logi_length >> blk_shift;
+ logical_unit = (fm_extent->fe_logi_length - 1) >> blk_shift;
+ if (flags & FIEMAP_EXTENT_UNKNOWN) {
+ physical_blk = 0;
+ physical_len = 0;
+ physical_unit = 0;
+ } else {
+ /* FIEMAP_EXTENT_DATA_COMPRESSED was checked by caller
+ * and fixed up fe_phys_length if unset. */
+ physical_blk = fm_extent->fe_physical >> blk_shift;
+ physical_len = fm_extent->fe_phys_length >> blk_shift;
+ physical_unit = (fm_extent->fe_phys_length - 1) >> blk_shift;
+ }
if (expected)
sprintf(buf, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
@@ -176,7 +190,8 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
print_flag(&flags, mask, buf, hex);
}
- if (fm_extent->fe_logical + fm_extent->fe_length >= (__u64) st->st_size)
+ if (fm_extent->fe_logical + fm_extent->fe_logi_length >=
+ (__u64)st->st_size)
strcat(buf, "eof,");
/* Remove trailing comma, if any */
@@ -184,10 +199,10 @@ static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
buf[strlen(buf) - 1] = '\0';
printf(ext_fmt, cur_ex, logical_width, logical_blk,
- logical_width, logical_blk + ext_blks,
+ logical_width, logical_blk + logical_unit,
physical_width, physical_blk,
- physical_width, physical_blk + ext_blks,
- ext_len, flags);
+ physical_width, physical_blk + physical_unit,
+ logical_len, buf);
}
static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
@@ -250,18 +265,29 @@ static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
if (!tot_extents)
tot_extents = 1;
}
+
+ /* If DATA_COMPRESSED is set, then the logical and
+ * physical extent lengths are different and the
+ * fe_phys_length field is known to be valid.
+ * Kernels older than 3.14 did not set fe_phys_length,
+ * so do that here to simplify the rest of the code. */
+ if (!(fm_ext[i].fe_flags &
+ FIEMAP_EXTENT_DATA_COMPRESSED))
+ fm_ext[i].fe_phys_length =
+ fm_ext[i].fe_logi_length;
+
if (verbose)
print_extent_info(&fm_ext[i], n, expected,
blk_shift, st);
-
- expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
+ expected = fm_ext[i].fe_physical +
+ fm_ext[i].fe_phys_length;
if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
last = 1;
n++;
}
fiemap->fm_start = (fm_ext[i - 1].fe_logical +
- fm_ext[i - 1].fe_length);
+ fm_ext[i - 1].fe_logi_length);
} while (last == 0);
*num_extents = tot_extents;
@@ -335,20 +361,22 @@ static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
count++;
if (force_extent && last_block != 0 &&
(block != last_block + 1 ||
- fm_ext.fe_logical + fm_ext.fe_length != logical)) {
+ fm_ext.fe_logical + fm_ext.fe_logi_length != logical)) {
print_extent_info(&fm_ext, *num_extents - 1,
(last_block + 1) * st->st_blksize,
blk_shift, st);
fm_ext.fe_logical = logical;
fm_ext.fe_physical = block * st->st_blksize;
- fm_ext.fe_length = 0;
+ fm_ext.fe_logi_length = 0;
+ fm_ext.fe_phys_length = 0;
(*num_extents)++;
} else if (verbose && last_block && (block != last_block + 1)) {
printf("Discontinuity: Block %ld is at %lu (was %lu)\n",
i, block, last_block + 1);
(*num_extents)++;
}
- fm_ext.fe_length += st->st_blksize;
+ fm_ext.fe_logi_length += st->st_blksize;
+ fm_ext.fe_phys_length += st->st_blksize;
last_block = block;
}
--
1.7.3.4
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
